<div class="doc-item" id="doc-1325"><h2 class="doc-item-name">set-validator!<span class="namespace">(clojure.core)</span></h2><ul class="var-arglists"><li>(<span class="var-name">set-validator!</span> iref validator-fn)</li></ul><div class="var-docstring"><p>Sets the validator-fn for a var/ref/agent/atom. validator-fn must be nil or a
  side-effect-free fn of one argument, which will be passed the intended
  new state on any state change. If the new state is unacceptable, the
  validator-fn should return false or throw an exception. If the current state (root
  value if var) is not acceptable to the new validator, an exception
  will be thrown and the validator will not be changed.</p></div><div class="var-source"><pre>; clojure/core.clj:1324
(defn set-validator!
  [#^clojure.lang.IRef iref validator-fn] (. iref (setValidator validator-fn)))</pre></div><div class="license"><p>Copyright (c) Rich Hickey. All rights reserved.</p><p>The use and distribution terms for this software are covered by the <a href="http://opensource.org/licenses/eclipse-1.0.php">Eclipse Public License 1.0</a>, which can be found in the file
          epl-v10.html at the root of this distribution. By using this software
          in any fashion, you are agreeing to be bound by the terms of this
          license. You must not remove this notice, or any other, from this
          software.</p></div></div>